Mozillaが提供する Magic GUID
if (pAccChild)
{
CComQIPtr<IServiceProvider> provider = pAccChild;
if( provider ){
const GUID refguid = {0x0c539790, 0x12e4, 0x11cf, 0xb6, 0x61, 0x00, 0xaa, 0x00, 0x4c, 0xd6, 0xd8};
CComPtr<ISimpleDOMNode> node;
provider->QueryService(refguid, IID_ISimpleDOMNode, (void**)&node);
CComQIPtr<ISimpleDOMDocument> ffdocument = node;
if (node) {
ffdocument->get_URL(&DOM_string);
if (DOM_string != 0) {
addressbar = (const wchar_t *)_bstr_t(DOM_string, FALSE);
}
}
ここでAccessibleObjectFromWindow
、プロバイダを取得するまでの間に、アクセス可能な階層を移動する必要がある場合がありますが、これは少し面倒です。
提案については、このCode Project - XMSAALibをご覧ください。
以下は、さまざまな問題をカバーするツリー ウォーキングの例です。ATL スマート ポインターを使用するようにオリジナルから変更され、いくつかのバグ修正 (または導入 ;) )
//-----------------------------------------------------------------------------
bool CXMSAALib::EnumAccessible(IAccessible *pIAccParent, IAccessibleEnumProc& lpEnumAccessibleProc )
{
_ASSERTE(pIAccParent);
// 2 ways to go through the children
// * some parents will support the Enum(erator) interface where child ids may not be a contiguous sequence, and children may be returned as id or IAccessible directly
// * others support the accChild function only where the count and ids should be contiguous.
CComQIPtr<IEnumVARIANT> pEnum = pIAccParent;
if( pEnum )
pEnum->Reset();
// get child count
long nChildren = 0;
if( FAILED( pIAccParent->get_accChildCount(&nChildren) ) )
nChildren = 0;
//TRACE(_T("nChildren=%d\n"), nChildren);
bool bContinue = true;
// skip 0 (self)
for (long index = 1; (index <= nChildren) && bContinue; index++)
{
HRESULT hr =0;
VARIANT varChildRef;
VariantInit(&varChildRef);
if (pEnum)
{
unsigned long nFetched = 0;
hr = pEnum->Next(1, &varChildRef, &nFetched);
//children may be returned as lVal id or IAccessible directly
if (!SUCCEEDED(hr) || !nFetched )
{
bContinue = false;
break;
}
}
else
{
varChildRef.vt = VT_I4;
varChildRef.lVal = index;
}
// IAccessible doesn't always allow indirect access to children that are also of type IAccessible
// change the focus to the child element if we can
VARIANT varChild;
VariantInit(&varChild);
CComPtr<IAccessible> pIAccChild;
FocusOnChild( pIAccParent, varChildRef, pIAccChild, varChild );
bContinue = lpEnumAccessibleProc(pIAccChild, varChild);
if ( bContinue
&& pIAccChild
&& CHILDID_SELF == varChild.lVal )
{
bContinue = EnumAccessible(pIAccChild, lpEnumAccessibleProc);
}
VariantClear(&varChild);
}
return bContinue;
}
//-----------------------------------------------------------------------------
bool CXMSAALib::EnumAccessible(HWND hwnd, IAccessibleEnumProc& lpEnumAccessibleProc)
{
if (::IsWindow(hwnd))
{
CComPtr<IAccessible> pIAccParent;
HRESULT hr = AccessibleObjectFromWindow(hwnd, OBJID_CLIENT, IID_IAccessible, (void**)&pIAccParent);
if (SUCCEEDED(hr) && pIAccParent)
{
VARIANT varChild;
VariantInit(&varChild);
varChild.vt = VT_I4;
varChild.lVal = CHILDID_SELF;
if( lpEnumAccessibleProc(pIAccParent, varChild) ) {
EnumAccessible(pIAccParent, lpEnumAccessibleProc, nLevel+1);
}
VariantClear(&varChild);
return true;
}
}
return false;
}
//-----------------------------------------------------------------------------
void CXMSAALib::FocusOnChild( IAccessible * pIAccParent, VARIANT &varChildRef, CComPtr<IAccessible> &pIAccChild, VARIANT &varChild )
{
// get IDispatch interface for the child
CComPtr<IDispatch> pDisp;
if (varChildRef.vt == VT_I4)
{
pIAccParent->get_accChild(varChildRef, &pDisp);
}
else if (varChildRef.vt == VT_DISPATCH)
{
pDisp = varChildRef.pdispVal;
}
// get IAccessible interface for the child
CComQIPtr<IAccessible> pCAcc(pDisp);
if (pCAcc && pCAcc != pIAccParent )
{
VariantInit(&varChild);
varChild.vt = VT_I4;
varChild.lVal = CHILDID_SELF;
pIAccChild = pCAcc;
}
else
{
pIAccChild = pIAccParent;
varChild = varChildRef;
}
}